黄芪总黄酮对急性心肌梗死大鼠心脏血流动力学及心肌细胞钙电流的作用

The effect of totalflavonoids of astragalus (TFA)on the hemodynamic of the left ventricula and calcium current of ventricular myocytes after the acute myocardial infarction

目的探讨黄芪总黄酮(TFA)对急性心肌梗死(AMI)大鼠心脏血流动力学及心肌细胞钙电流的作用。方法大鼠开胸左前降支结扎造成AMI,开胸前5min实验组大鼠舌静脉注射剂量为(20mg/kg)TFA溶液50μl,并设正常对照组,AMI组及TFA实验组,后行血流动力学检查;酶解分离心室肌细胞,采用全细胞膜片钳记录技术记录左前降支供血区心外膜细胞的L型Ca2+电流(L-Ica)的作用。结果①应用TFA(20mg/kg)后与AMI组比较,血流动力学指标明显改善(P<0.05,n=7)。与正常对照组相比差异无统计学意义(P>0.05,n=7)。②应用TFA(20mg/kg)后与AMI对照组比较,L-型钙电流(L-ICa)由给药前的(0.31±1.09)nA增加到给药后的(0.49±0.89)nA(P<0.01,n=7)。结论TFA可以明显改善AMI大鼠心脏血流动力学,增加心室肌细胞L-型钙电流的幅值。

Objective To study the effect of totalflavonoids of astragalus （TFA） on the hemodynamic of the left ventricula and on calcium current of ventricular myocytes after the acute myocardial infarction. Methods The rat was used to be studied, proceed with administration by injection from tongue vein on the groups of control, TFA and AMI 5 min, acute myocardium infarction model were prepared. The AMI rat recorded the changes of LVP and LVdp/dtmax, whole cell patch clamp technique was applied to record the L-calcium current （L-Ica） of rat isolated ventricular myocytes from ischemic zone adjacent to infarcted area. Results （1）Compared with the AMI group, the TFA（20 mg/kg） group significantly enhanced the hemedynamic of the left ventricula after the acute myocardial infarction（P〈0.05, n=7）,there is no significant difference the TFA（20 mg/kg） group compared to control group（P〉0.05 ,n=7）.（2）Compared with AMI group, the TFA（20 mg/kg）enhanced the calcium current from （0.31±1.09）nA to （0.49±0.89）nA （P〈0.01 ,n=7）. Conclusion TFA can significantly improve the hemedynamic of the left ventricula after the acute myocardial infarction, TFA enhanced the L-calcium current of ventricular myocytes after the acute myocardial infarction.